Microsoft executives already are counting their Vista chickens before the next-generation Windows release has hatched. A Microsoft vice president on Feb. 1 detailed for attendees of the Merrill Lynch IT Services & Software Conference Microsoft's reasons for its high expectations for Vista, the release of Windows client due to ship in the latter half of this year. Microsoft expects 200 million new PCs to ship with Vista preloaded in the first 24 months that the operating system is available, said Michael Sievert, corporate vice president, Windows Product Management & Marketing.